Addition and Subtraction
Addition means combining two or more numbers to find a total. Subtraction means taking away one number from another to find the difference.
Column method
To add two-digit numbers, line them up by place value and add each column starting from the ones. For example, 47 + 25: add the ones (7 + 5 = 12), write down 2 and carry the 1. Add the tens (4 + 2 + 1 = 7). The answer is 72.
Practice
Try these: 36 + 28, 54 - 19, 82 + 17.